This invention relates to protection of an area of a lightweight alloy vehicle wheel such as one of aluminum, particularly a replaceable wear protector suitable for use in the bead seat area of the wheel, particularly an aircraft wheel.
Aluminum alloy wheels have come to be widely employed in many aircraft, truck and automobile applications. Currently such wheels are protected by anodizing and/or painting. When placed in service with a tire mounted thereon, a chafing action occurs in the beadseat area. This chafing action wears away the protective anodize and/or paint layer. Once unprotected, this beadseat area is susceptible to attack by elements and debris in the environment, particularly chemical attack resulting in corrosion. The beadseat area is subject to high stresses which accelerates corrosion and increases the risk of fatigue failure initiated at the corrosion pits. Many wheels must be removed prematurely from service due to corrosion pitting in the beadseat area.
Past attempts to rework such corroded areas have included machining away the corroded material, spraying on new metal, and a second machining operation to restore the desired contour. This past repair technique has proven unacceptable due to the possible development of fatigue cracks beneath the newly applied metal which are undetectable upon non-destructive examination of the repaired beadseat surface. These hidden cracks can progress to cause structural failure of the beadseat area even though the surface metal shows no evidence of deterioration. According to another known approach, aluminum alloy aircraft wheel halves have in the past been repaired in local areas including the beadseat area by removal of scratches, nicks, corrosion or other minor surface damage by locally blending the damaged area using fine abrasive cloth, e.g., 320 grit or finer. Damaged packing seat surfaces, e.g., where "O" rings seal valve stems or wheel parts to other parts, have been repaired by blending the damaged area with a hand file, cleaning away any contaminants with solvent, shot peening the reworked area and filling the repair area that has been filed away with an aluminum-filled epoxy such as that available under the trademark Devcon F from Devcon Corp., Danvers, Mass. After the metal-filled epoxy has hardened, the surfaces are again blended and smoothed by hand to restore the original configuration.
The present invention provides a wheel having a replaceable beadseat protector which protects the beadseat area from tire abrasion and chafing and subsequent corrosion. When formed of organic resin material, the wear protector also reduces transfer of heat through the beatseat area of the wheel and the associated tire. The beadseat protector can be removed and replaced periodically as required. Because the beadseat protector is a separate component that is affixed to the beadseat area, the structural integrity and fatigue strength of the base wheel material is unaffected by its presence. The beadseat protector may be constructed form a variety of materials including ferrous and non-ferrous metals and plastics. It is preferably prepared from fiber-reinforced organic resin which is premolded to the desired internal and external contours for the intended application. The wear protector is sealingly affixed to the beadseat area against rotation relative to the wheel rim, by bonding or by mechanical interference.